人为的和自然环境中的污染物对人类健康和各种生态系统的可持续发展构成了不同程度的威胁。当有毒的污染物被排放到河流生态系统中，很多物质会进行扩散、沉淀以及受到水流从上游往下游的冲刷，污染物在河流各个区域的浓度分布会受到水流的流量、流速以及河流自身的水文结构等因素的影响。为了研究污染物对河流生态系统中的单个种群以及多个种群间相互作用的影响，本项目将结合河流的水文特征和种群的动力学行为，建立并研究一系列的数学模型，包括反应-扩散-对流方程模型、一维和二维的底层-漂流层模型等。通过对模型解的适定性、稳定性、行波解、R0分析等理论分析，以及利用有限差分、R0计算的配点法等数值方法，结合实际数据，探索污染物在河流生态系统的时空分布以及河流自身的水文特征对种群的持续生存、食物链的完整性和种群多样性的影响机理。此课题的研究成果将为水文、环境和生态工作者提供值得借鉴的理论参考依据。

Anthropogenic and natural environmental contaminants affect human health and ecosystem persistence in varying degrees. After being released into river ecosystems, toxic contaminants may disperse, deposit or being washed from upstream to downstream, the concentration of contaminants at different locations are different due to the effects of discharge, flow velocity, and stream hydraulic characteristics. To study the effects of environmental contaminants on single population dynamics and interactions between species, we will develop several models by considering hydraulic characteristics of rivers and population dynamics. The models include reaction-diffusion-advection equation models, 1D- and 2D- benthic- drift models. The results of theoretical analysis, such as well-posedness, stability, traveling wave solutions, R0 analysis, and numerical methods including finite difference and collocation method for calculation of R0, combined with real data, will be used to investigate how the environmental contaminants and hydrolic characteristics of rivers impact population persistence, integrity of food webs, and population diversity. The theory developed here will provide the basis for effective decision-making tools for water managers, environmental scientists, and ecologists.